DISCUSSION
Today, sleeping habits of children are in the focus of not only pediatricians but dentists as well. The relationships between sleeping habits and possible TMJ problems, malocclusion, TDI, bruxism and dental caries have been investigated recently and still holds a major area of research interest.(15-17)
In this study, Turkish Version of CSHQ was used for data colletion. This questionnaire was translated to Turkish and validated and reported to be a reliable instrument for assessing sleep habits and screening possible sleep problems of Turkish children.(18)Although there are various concerns that parent’s notifications may differ from the child’s self-report, scales based on parents’ reports are frequently used in both psychiatry and pediatric practices.(19)It is noteworthy that, American Academy of Sleep Medicine considers the reports of parents to be reliable and sufficiently objective for use in epidemiological studies.(8)
In the present study, prevalence of sleep bruxism was found 40%. However bruxism prevalance among children displays a fluctuating pattern.(4,9,11,20) In a systematic review by Machado et al., the prevalence rates of sleep bruxism vary from 5.9% to 49.6%, and these variations show can be attributed to different diagnostic criteria used for bruxism.(9) Therefore, evidence-based studies with standardized and validated diagnostic criteria are required for accurate assessments. (9)Insana et al. reported that sleep bruxism affected more boys than girls.(20) In the study by Cheifetz et al., there was also a trend for males to be more likely to brux than females.(11) However, in the present study no significant relation was found between presence of sleep bruxism and gender.
Potential sleep bruxism is hereditary. Muscle pains, snoring and mouth breathing are important signals for detecting sleep bruxism in children. Sleep fragmentation was also found associated with sleep bruxism.(29) Nocturnal agitation and nightmares were found to be associated with possible nocturnal bruxism. Moreover, young children with evening chronotype were reported to have an tendency toward possible sleep bruxism.(30)
In the present study, nocturnal bruxism was found to be associated with sleeping habits. The presence of bruxism was significantly higher in child who had bedtime difficulties. In parallel to this finding, Oner et al. reported that sleep quality was associated with nocturnal bruxism in children.(21)
9% of the children showed TMJ disorder symptoms in the present study. TMD prevalence in children and adolescents vary from 16 to 68%.(22) Mostly, study populations’ subjective TMD symptoms were jaw clicking , muscle tenderness, pain on opening and limited opening.(11)
In the present study, there was a statistically significant relationship between TMJ disorders symptoms with sleeping characteristics and and bruxism. Children with bed time resistance were more likely to have TMD disorder symptoms. In contrast to our findings, Cheifetz et al., reported that TMD symptoms were not associated with bruxism.(11) However, our findings were in line with Lei et al. that reported TMD symptoms were significantly associated with psychological distress and disturbed sleep.(23)
When functional changes that occur with factors such as occlusal conflicts reach a certain level, they begin to produce textural changes. In the present study, the prevalence of malocclusion was found 62% among children, and Class I was the most frequent molar relationship (79%). Numerous studies have been published on the prevalence of malocclusion with reported prevalence ranging from 39% to 98%.(24,25) Our result is in line with Sayin et al., reporting that Class I was the most frequently seen malocclusion in Turkish orthodontic population.(26) However, no significant relation was found between malocclusion and sleeping habits which may be attributed to limited sample size.
Factors such as traumas and parafunctional habits can change the existing structural tolerance of TMJ. In this study, the prevalence of traumatic dental injury was 22%. In a study by Carvalho et al., the overall prevalence of dental trauma was found %37.1 in school-children.(27) No significant correlation was found between sleep disorders and traumatic dental injuries in our study. Based on previous literature, traumatic dental injuries tended to be associated with sleep disorders. Sleep disorders in children can affect motor skills, cognition and concentration. A bad night sleep can affect a person’s mood and concentration the next day.(17) It was stated that sleep deprivation was associated with accidental injuries; 86% increase in trauma incidences when children slept less than 10 hours the night before the accident.(28) In addition, waking up three to four times at night, which is an indication of agitated sleep, was associated with a higher traumatic dental injury prevalence.
Daytime sleepiness is the main aspect of sleep behavior associated with the prevalence of traumatic dental injuries and dental caries.(17,31) The prevalance of dental caries is very high in the present study which unfortunately reflects the unmet oral health care in Turkey(32) Subsequently, retardation in growth, missing of school and fragmentation of sleep is inevitable.(33) Dental caries was found associated with sleep fragmentation in the present study which is also in line with previous reports.(31,33)
It should be noted that various limitations should be considered when interpreting the data in this study. Sleep disorders and bruxism was evaluated based on the subjective judgment of parents. The role of the family is very important in the diagnosis of pediatric nocturnal bruxism cause it occurs by recognizing the characteristic sounds produced by the grinding of teeth at night.(4) Therefore, although parents’ answers are subjective in this study, it is the most appropriate method to collect data for reliable and large sample studies.
The relationship between sleep problems and higher bruxism and temporomandibular disorders prevalence suggests that sleep samples should be investigated in scientific research using other methodological diagnostic methods to confirm these findings. In this manner, data on sleep behaviors obtained when collecting the patient’s history before a dental appointment can be useful for a better orientation to parents in preventing bruxism and temporomandibular disorders. Consequently, integration with paediatricians, pedodontists and psychiatrics is the key factor to diagnose, treat and avoid sleep related oral health problems.